Objective To investigate the dynamic changes of vascular adventitia and collagen distribution in the vein graft restenosis model, and evaluate the effects of adventitia and collagen distribution on intimal hyperplasia and vascular remodeling. Methods The pig autogenous vein grafts restenosis model from 18 longwhite pigs were created. 18 pigs were divided into 3 groups: 7th day group after operation, 30th day group after operation and 45th day group after operation according to animals harvested after surgery. The preoperative graft was as control group. According to HE and Masson staining slices, the vascular thickness, cell density, collagen distribution and vascular remodeling were investigated by histomorphometrical approach. Results In 7th day group after operation, the neointima formed and continuously thickened. The thickness and cell density of adventitia increased gradually, and the collagen of adventitia and neointima gradually increased, the luminal area gradually decreased after operation, but have no significant difference with control group（F=2.03,P=0.091）. The residual restenosis rate increased inversely（F=5.16,P=0.033）. Remodeling index and external elastic lamina area (EELA) slightly increased. In 30th day group after operation, the neointima thickened significantly, the thickness and cell density of adventitia reached the peak. There were a significant increase in the collagen of neointima, and the collagen of adventitia reached maximum. The luminal area and inter elastic lamina area(IELA) reduced distinctly as compared with 7th day group, the residual restenosis rate increased significantly（F=6.63,P=0.018）, but remodeling index and EELA decreased distinctly as compared with 7th day group after operation. In 45th day group after operation, the thicknessof neointima reached maximum, but the cell density of adventitia reduced distinctly compared with 30th day group after operation（F=6.91, P=0.015）. The collagen of neointima reached maximum, but the collagen of adventitia were smaller than those in 30th day group after operation, and there were some local fibrosis in adventitia. The luminal area, remodeling index, IELA and EELA reached minimum, but the residuum restenosis rate reached maximum. Conclusion Vein grafts restenosis is resulted by intimal hyperplasia and vascular remodeling. The thickness and fibrosis of adventitia and rearrangement of collagen are the important factors on intimal hyperplasia and vascular remodeling, which takes part in and accelerate the course of vein restenosis.
Objective To evaluate the left ventricular remodeling after valve replacement for valvular heart disease with giant left ventricle. Methods The clinical material of 92 patients with valvular heart disease and giant left ventricle after valve replacement was retrospectively reviewed. The results of ultrosonic cardial gram（UCG） and the changes of cardiac function before and after operation were compared. Results There was no operative death. The value of left ventricular end-diastolic dimension （LVEDD）, left ventricular end-systolic dimension （LVESD）, left atrial dimension （LAD）, left ventricular ejection fraction （LVEF）, left ventricular fractional shortening （LVFS）, stroke volume （SV） and cardiothoracic ratio in 2 weeks and 2 months after operation were more decreased than those before operation（P〈0. 05）. The value of LVEDD and LAD in 2 months after operation were much more decreased than those in 2 weeks after operation （P〈0. 05）. The cardiac function in early stage after operation was more decreased than that before operation,but the cases of cardiac functional class Ⅱ （38 cases, 41.3% ） in 2 months after operation was significantly more than those before operation （5 cases, 5.4 % ）. Conclusions The early effect of left ventricular remodeling is significant for valvular heart disease with giant left ventricle after valve replacement. The diameter of left ventricle and left atrial are significantly decreased after operation. The protection for cardiac function should be carefully taken in order to prevent the occurrence of complication after operation.
Abstract:Objective To investigate the reoperation indication,surgical timing and the key point of surgical treatment of prosthetic valve endocarditis （PVE） after valve replacement. Methods From February 2000 to July 2005,18 patients with PVE underwent surgery ,their clinical manifestation ,process of treatment and their prognosis outcome were analyzed. Results There were 3 patients （16.7 %） of early-death, 1 patient died of septic shock, and 2 patients died of multiple organ failure. Since 2003,there was no operative death for all 11 patients. There were 6 patients with respiratory insufficiency, 2 patients with renal insufficiency,which were recovered after treatment. The 15 survivors were followed up from 1 month to 5years. There was recurrence of infection in 1 patient who died after ineffective medical treatment. The other 14 patients recovered well. Conclusion It has high risk and high mortality for reoperation for PVE. Accurate reoperative indication,optimal surgical timing,radical debridment of infected tissue and correct perioperative use of antibiotics are the key factors to improve the reoperative result for PVE.
Objective To summarize experience in surgery about off-pump coronary artery bypass grafting(OPCAB)for the treatment of left main with three-vessel coronary disease. Methods OPCAB were perfomed in 33 patients of left main with three-vessel coronary disease. The left internal mammary artery(LIMA) was used to be the graft vessel to anastomose with left anterior descending. The saphenous vein was used to be the graft vessel to anastomose with left circumflex coronary artery, right coronary artery/posterior descend artery, diagonal branch, obtuse marginal branch. Results There was no operative death.The average number of grafting was 3.4 per case.There was no perioperative myocardial infarction, respiratory or hepatic or renal failure and other serious complications.Blood transfusion was not needed in 33% of cases.The angina pectoris was free after operation in all cases. Conclusions OPCAB is safe and effective for the treatment of left main with three-vessel coronary disease. The injuries were minimal. Preoperative preparation, using of intra-aortic balloon counterpulsation, operative matching, techniques and to create a skill and swift team for meet an emergency are the key factors to assure surgical outcome.
Objective To investigate the expression of neutrophil gelatinase-associated lipocalin (NGAL) signaling pathways in the early stage of porcine vein graft restenosis, and to explore the possible role and mechanism in the early vein graftrestenosis after coronary artery bypass surgery. Methods We selected 18 ordinary healthy pigs weighing 25-30 kg and collected samples of the vein graft of pigs at the preoperation and postoperative days 7, 14 and 30. Hematoxylin-eosin (HE) staining and Masson staining, immunohistochemical method were used to observe the neointimal hyperplasia, the migration of smooth muscle cells and and vascular remodeling of the vein bypass graft. The expression changes of NGAL, matrix metalloprotenase (MMP)9, MMP2 and tissue inhibitor of metalloproteinase (TIMP)1 in different periods of the vein bypass graft was tested. Results By HE and Masson staining, with the passing of modeling time, degradation of collagen matrix in the vein graft, gradually thickening of muscle fibers and the migration to the inner membrance and vascular remodeling caused the vascular stenosis. By immunohistochemistry, NGAL, MMP9 and MMP2 of normal vein in the model were seldom expressed and even did not express. At 14 days after the modeling, NGAL expression in the membrane layer of blood vessels began to appear, peaked at postoperative 30 days, and began to appear in the inner membrance. MMP9, MMP2 expression began to appear at postoperative 7 days, peaked at postoperative 14 days, and tended to decline at postoperative 30 days. TIMP1 expression was less in normal vascular walls and at the 14 days after the modeling, expression peaked in the vein graft. Conclusion NGAL, MMP9, MMP2 and TIMP1 may be involved in the formation of early vascular graft restenosis. NGAL as initiator, results in the expression of MMP9 and MMP2, and participates in the degradation of collagen matrix and the migration of smooth muscle cells in vein grafts. TIMP1 as a negative factor, may play an important role in maintaining their own balance.